Combustion engine powered leaf blowers are used more and more for different kinds of work. The numbers of areas where leaf blowers are used is increasing and the leaf blowers are replacing traditional brooms. Leaf blowers are an effective and time saving tool for cleaning of large areas like, for example, parking places, pavements, lawns and footpaths.
Leaf blowers make it possible to clean large areas in an easy way. During cleaning of areas with conventional equipment, parked cars in a parking place will make it necessary to leave parts of the area uncleaned. If the same area is cleaned with a leaf blower, it is possible to blow away the rubbish underneath the parked cars, which will increase the efficiency, save time and improve the result.
Even though the leaf blower is an effective tool that helps the operator to clean large areas, the operator will work long shifts carrying the leaf blower on the back. Leaf blowers available on the market today are large and heavy, with the center of gravity of the tool placed at a long distance from the back of the operator. This will subject the operator to high loads when the leaf blower is carried on the back of the operator. This type of tool also generates a lot of noise, which will make it very tiring for the operator as well as for other persons located close to the tool.
A leaf blower comprises at least a fan with a fan wheel, an engine and a couple of other details that are necessary to make the leaf blower work properly. The leaf blowers that are designed to be carried on the operators back that are available on the market today is designed with the fan and the fan wheel closes to the operators back and secured to a supporting frame for example made of pipes or shaped like a plate. The straps for carrying the leaf blower are secured in the supporting frame. Air to the fan is sucked into an inlet placed on the side of the fan that is turned toward the back of the operator. There must, therefore, be a gap of about 5 to 10 centimeters between the back of the operator and the inlet to the fan to guarantee that enough air will reach the inlet. The engine is then placed on the fan wheel axle on the side of the fan wheel that is turned away from the back of the operator.
A leaf blower designed like this will have a center of gravity placed at a long distance from the back of the operator. The distance between the center of gravity of the tool and the back of the operator is very important since it is related to the load that the operator is subjected to, as well as how easy it is to handle the tool. This distance should be as short as possible in order to minimise the loads on the operator.
There are several different leaf blowers available on the market, but all of them have some sort of supporting fame. To this supporting frame, often made of pipes or plates, different components in the leaf blower are attached. Some of these components may be provided with a cover that protects the component or for reducing the noise that is discharged from the component. Drawbacks of these known solutions are that they are heavy, take a lot of space and are not considered to be effective in lowering the noise level around the tools. This type of leaf blower is illustrated in U.S. Pat. No. 5,195,208.